1. Field of Invention
The present invention relates to a butt type contact terminal employed in a power supplying connector in an electric car, for example, and having a structure in which a sliding contact member is adapted to slide by way of a coil spring when the connector is engaged or disengaged, and also to a connector employing the same.
2. Related Art
FIG. 6 shows a conventional butt type contact terminal.
This butt type contact terminal 61 is used in the power supplying connector of the electric car, for example, and includes a front end portion 62 and a rear end portion 63 made of conductive metal, a braided wire 64 for connecting the front end portion 62 to the rear end portion 63, and a coil spring 65 resiliently provided between the front end portion 62 and the rear end portion 63 for expanding the braided wire 64.
The braided wire 64 is press-fitted and connected to the front end portion 62 and the rear end portion 63. An electric wire 66 for power supply is connected to the rear end portion 63. When the power supplying connector (not shown) having the butt type contact terminal 61 is connected to the power receiving connector (not shown) in a vehicle, the front end portion 62 of the terminal 61 is abutted against a terminal of the power receiving connector to retreat against a biasing force of the oil spring 65, and at the same time, the braided wire 64 is contracted. Electric current flows from the electric wire 66 to a contact 62a at a forward end of the front end portion 62 by way of the braided wire 64, and from the contact 62a through the power receiving connector to be charged into a battery in the vehicle.
However, in the above described conventional butt type contact terminal 61 and the connector employing the same, the braided wire 64 is passed inside the coil spring 65, and the front end portion 62 and the rear end portion 63 must be press-fitted and connected to the braided wire 64 in a state where the coil spring 65 is contracted. Therefore, there have been such a problem that an annoying assembling work is required, thus, incurring a high cost.
In addition, because on each occasion of battery charging, (each time when the power supplying connector and the power receiving connector are engaged with and disengaged from each other), the braided wire 64 is expanded and contracted, it has been a problem that the braided wire 64 is apt to be cut, and electric resistance is increased resulting in a deterioration of electrical efficiency. Moreover, in case where the terminal and the connector are splashed with muddy salt water on occasion of the battery charging, it has been a problem that impurities such as mud or salt, etc. are adhered to the braided wire 64 to cause rust, and the electric resistance is increased resulting in a deterioration of the electrical efficiency. The muddy salt water generally occurs through freeze-proof activity or so, on road, for example, in the winter season.
In view of the above described problems, it is an object of the invention to provide a butt type contact terminal and a connector employing the same which will not increase electric resistance after repeated contacts with a mating connector, can always maintain favorable electric efficiency, can be easily assembled and manufactured at a low cost, and will not be affected by muddy salt water even though they are splashed with the muddy salt water.
In order to attain the above described object, the invention employs a butt type contact terminal characterized in that it comprises a terminal body connected to an electric wire, a sliding contact member slidably engaged around an outer periphery of the terminal body and having a contact portion with respect to a mating terminal at its forward end, and a resilient member resiliently provided between the terminal body and the sliding contact member, either one of the terminal body and the sliding contact member being provided with a plurality of elastic contact pieces arranged in a circumferential direction by way of axial slits, and a forward end of the terminal body and a rearward end of the sliding contact member being respectively provided with projections for engagement and contact therebetween.
It is also effective that the terminal body includes an elastic contact portion in a substantially cylindrical shape having a plurality of the elastic contact pieces, a flange portion extending from the elastic contact portion, and an electric wire connecting portion extending from the flange portion.
It is also effective that the sliding contact member includes a peripheral wall in a substantially cylindrical shape having the projections inwardly, a covering wall formed at a front end of the peripheral wall, and the contact portion provided on the covering wall so as to project therefrom.
Further, it is also effective that an outer diameter of the elastic contact portion in a free state is set to be larger than an inner diameter of the peripheral wall, whereby in a state where the elastic contact portion is inserted into the peripheral wall, the elastic contact portion is elastically brought into contact with an inner face of the peripheral wall.
Still further, it is also effective that the resilient member includes a coil spring which is resiliently provided between a rear end of the peripheral wall of the sliding contact member and the flange portion of the terminal body.
In addition, the invention also employs a connector employing the butt type contact terminal wherein at least one of the butt type contact terminals according to the present invention is inserted into a connector housing, the flange portion is locked by locking lances formed in the connector housing, and a waterproof packing is tightly fitted to the contact portion and to the electric wire.